Polyacetal resins, which are engineering plastics, have excellent mechanical property, sliding property, frictional and wearing properties, heat resistance, molding processability, and the like. For this reason, polyacetal resin compositions containing polyacetal resins have been widely used for, for example, various machine components or electrical components of automobiles, OA instruments, and the like.
However, since formaldehyde is used as a main raw material of the polyacetal resin, the polyacetal resin is slightly thermally decomposed by thermal history in molding processing and the like. Thus, although in a very minute amount, formaldehyde is generated. Herein, since there is a possibility that sick house syndrome or the like may occur due to formaldehyde, there is a demand for a polyacetal resin composition in which generation of formaldehyde is sufficiently suppressed.
As such a polyacetal resin composition, a polyacetal resin composition disclosed in Patent Document 1 described below is known. Patent Document 1 described below discloses a polyacetal resin composition obtained by blending a dihydrazone compound with a polyacetal resin at a predetermined ratio, and proposes that with use of this polyacetal resin composition, the generated amount of formaldehyde generated from a product is reduced and contamination of a mold at the time of molding process is also suppressed.